Well, I suppose many of you folks will recall that I'm kind of a curmudgeon with regard to rechargeable batteries. For the most part I am a big fan of CR123a and gravitate towards devices that will use them. Short of that I like lithium AA & AAA devices.

But a year or two ago I got a Petzl lamp with a CORE battery pack. It's a compact replacement for the three AAA batteries that most of Petzl lamps use and charges via a micro-USB port. After using it quite a bit I have found it be pretty good quality and easy to use.

Recently I made a big step and bought a Cloud Defensive OWL weapon light. This required a bit of soul searching as it requires an 18650 battery; indeed, using CR123A will void the warranty! The new breed of uber-WMLs have gone this route and the future seems to be rechargeable. As with so many things in our modern age, it's a replay of the various arms races and horsepower wars of the past.

An IT instructor of mine always used to tell me you gotta go with the new meaning you need to be familiar with current tech and keep up to insure compatibility. So I have kind of tried to go in for a crash course in battery tech. The OWL ships with 2 batteries (a Samsung 30Q and a 3500 mAH Sanyo) as well as a solid basic charger. If I'm going to rely on these cells I want to get a more advanced charger that can do more diagnostics on the internals of the batteries to ascertain their health. So far I picked up another pair of 30Qs and have a Murata VTC6 on the way as well as a Samsung 25R and another of the NCRs that shipped with the light.

I guess in for a penny, in for a pound! While I will likely always have a large stash of lithium primaries for the things they do uniquely well I want to dive into rechargeables to a greater extent. In the long run they save some money and more importantly will be a greener option that using a lot of disposables that work once and then head to a landfill.

My WLM needs 18650s with flat tops, and I will likely stick to known cells since reliability is my top priority. But I have a high powered JETBeam that uses button top 18650s and will prioritize 18650 and maybe 21700 use for future purchases. Also I will probably delve into AA & AAA, and was thinking LADDA and Eneloops but I'm not really very up to date on what's the best.

That said, I am looking for advice! Can anyone suggest a good charger for 18650 that is versatile and with good testing and diagnostics? I prefer something as simple and intuitive as possible although I'm realistic re Chinese chargers. And any advice for good quality batteries would also be appreciated!

I would agree with your observations about the advantages of rechargeables vs. traditional throwaways.

My principal charging device is a Nitecore intellicharger i4 which will do NiMh AA, AAA, AAAA, and C, as well as a whole passel of li-ion sizes including 18650s, but not 21700s, in increasingly common offering. It gets power from the wall or also 12V cigarette lighters. I am happy with it.

I also hav some Fenix AAs with built-in chargers; they are powered with an integral micro-USB port. They offer the same in other sizes. The advantage here is that you only need a power bank and appropriate cable to recharge them.

I am currently focused on light weight, minimal rigs suitable for backpacking and isolated camping. Eventually I want to go big and have more juice to more effectively deal with the now common power outages (better than wild fires!).

As far as I am concerned, alkakines are obsolete Stone Age relics, although there is a place for disposable lithium batteries....

It depends on power source, if talking regular wall socket...

Vapcell S4 Plus https://www.vapcelltech.com/h-pd-20.html

It'll charge the common lithium ion sizes, and also the NiMh (LADDA/Eneloops) AAA & AA.

I only have one charger that will handle an 18650, been using it for a few years, and I'm happy with it. The "Nitecore D2". Never a problem. Is it better or worse than others? I don't know - it's the only 18650 compatible charger I own. It is inexpensive, and will charge everything I have (LiION, NiMH). It is not large enough to do 21700's though (I don't have anything that uses that size battery).

https://www.nitecorestore.com/NiteCore-D2-DigiCharger-Universal-Charger-p/chg-nite-d2.htm

I have personally used it with 18650's, 14500's, 16340's, AA NiMH's, and AAA NiMH's

The other charger I use, but it only does AA and AAA NiMH's, is a "Maha MH-C401FS". It is many years old - I can't believe they still make it, but apparently they do. But it still works as well as the day I bought it.

https://mahaenergy.com/mh-c401fs/

For batteries, I use the Nitecore 18650 3400mAh (they now have a 3500mAh model that they didn't have when I bought mine). The 16340's I use are Fenix brand 700mAh (these have a little microUSB port so you can charge them with a phone cord if you want, but I've never done that). The 14500's are 750mAh AW brand (many years old, but still work great), and the AA and AAA NiMH's are Eneloops.

Yeah, I haven't bought an alkileak in decades! Got tired of leaking batteries ruining expensive electronics. The last straw was years ago needing a pliers and corkscrew to remove a badly leaking Duracell from an expensive-for-the-time point and shoot camera. The charger I have is a Nitecore IICR but branded for Cloud Defensive. It works fine but I want to be able to track internal resistance and measure capacity to keep track of battery degradation.

Not a bad price, either! Thanks!

Thanks! I'll check into the analyzer models.

I keep one of the gigantic Costco packs of alkaline AA's for one specific emergency use. As a backup power source for my Yaesu FT-60R HAM transceiver.

Normally, this radio is powered from it's OEM battery pack (NiMH technology - this radio is an old design and does not use LiION).

First line backup power is Eneloop AA's in it's optional accessory battery holder. Note: The instruction manual specifically says not to use NiMH's in the optional accessory battery holder. However, what they are warning against is not to put the NiMH's in that holder and then use the Yaesu charger to charge them. It is fine to charge the individual NiMH's in a separate charger (like my Nitecore or Maha mentioned above) and then put those charged batteries in the accessory battery holder. My guess is that the Yaesu charger is a crappy one, containing no protection circuitry to prevent overcharging, overheating, etc. They depend on the OEM battery pack to provide those features. But the accessory battery holder loaded with your own NiMH's would not provide those features. Thus the warning not to use that setup with the Yaesu charger. It would have been better for the instruction manual to say "Do not charge NiMH's in the Yaesu accessory battery holder", but instead they said "Do not use..." I guess you'd call that "Out of an abundance of caution...". Disclaimer: I did not ask Yaesu about this, I am speaking from my Electrical Engineering background. There is no reason that their OEM NiMH battery pack would be different than their accessory battery holder loaded with your NiMH batteries - save for protection circuitry that they may have included in their OEM pack.

Second line backup power for the radio is that Costco package of Alkaline AA's. There's got to be 40 or more batteries in that package (typical for a Costco item!) I would not leave those alkaline batteries in the radio. They are only a last resort emergency backup to power the radio should all other sources of power be exhausted. I also still have a few AA sized LED lights that could use those batteries as a last resort emergency backup as well.

I have been using rechargeable AA and AAA batteries, Eneloop Pro charged in an older Eneloop charger. Gets the job done, but I am sure it's very basic.

Nitecore D2 Digicharger and D4 Intellicharger... hooked up to a power strip so they can be run off a single circuit when used with the generator... converted to the Sanyo/Panasonic AA Eneloops after the 2004/05 hurricane season for light and radio power, and still using the same cells... for the WML I use 123's as a couple of the pistols have the parallel battery configured Streamlight TLR-1 light

I use the AAs for task and area lights, but the 6P size bodies with Solar Force heads/modules and Malkoff module still get factory 123s